For example, as for a manufacturing process of semiconductor devices, when a process such as an etching process, a film forming process or the like is performed on a semiconductor substrate, a processing gas and/or a reaction product (hereinafter, referred to as “contaminant components”) from the process remain on a surface of the semiconductor substrate and are then gasified. Such gasified contaminant components may contaminate the surrounding environment of the semiconductor substrate. For that reason, by keeping the processed semiconductor substrate for a time period in a vacuum environment or an environment in which a gas flows (hereinafter, referred to as “purge process”), the contaminant components are removed from the semiconductor substrate by evaporation or the like. Thereafter, the semiconductor substrate may be accommodated in a FOUP and subjected to a next process.
However, in case that a large amount of gas is generated from the semiconductor substrate, the gas is attached on a part of the processing apparatus, so that the part may be corroded or peeled off, resulting in producing particles, for example. Further, it may be difficult to perform the vacuum process depending on the specifications of the processing apparatus. In this case, it takes a long time to perform the purge process, thereby lowering the throughput of the processing apparatus.
Although a method for cleaning a substrate by using a liquid may be suggested to remove the contaminant components, this cleaning method can cause a pattern collapse to occur due to the surface tension of the liquid in an etched pattern or a resist pattern that has been made increasingly fine recently.
Accordingly, a resister removing method has been suggested (see, e.g., Japanese Patent Application Publication No. H06-181050 (JP06-181050A)). Specifically, in a fine pattern forming process where a resister is coated on the surface of a substrate to form a pattern by employing a lithographic approach, a part of the substrate on which the resister is attached is soaked in a supercritical fluid to remove the remaining resister.
Further, an aerosol cleaning method for cleaning a target substrate by spraying an aerosol to the target substrate has been suggested (see, e.g., Japanese Patent Application Publication No. 2003-209088 (JP2003-209088A)). In the aerosol cleaning method, a supercritical state or a pseudo-supercritical state is locally created on the surface of a target substrate to be cleaned by spraying the aerosol to the target substrate at a high speed, to thereby improve the cleaning performance.
However, the cleaning process using the supercritical fluid disclosed in JP06-181050A is required to be performed in a high-temperature and high-pressure state. This results in a complex configuration. Further, the aerosol cleaning method disclosed in JP2003-209088A requires a spraying device for spraying an aerosol at a significantly high speed to a target substrate. This requires the apparatus to be scaled up and more complex. Moreover, the high-speed aerosol can damage the pattern formed on the substrate.